1. Field of the Invention
The present invention is broadly concerned with improved, prefabricated curb assemblies designed to be mounted on standing seam roofs (which are traditionally formed of metal). More particularly, the invention pertains to the curb assemblies and overall roof constructions with curb assemblies mounted thereon. The curb assemblies are specially designed for rapid and easy field installation, while providing a rigid, water-tight, peripherally sealed construction.
2. Description of the Prior Art
Roof curb assemblies have been in use for many years for the purpose of mounting roof fixtures, such as exhaust fans, skylights, or air conditioning components. Generally speaking, these curb assemblies include upstanding box walls, which are secured to the underlying roof and in surrounding relationship to an opening formed in the roof and associated with the mounted fixture. In some instances, roof curb assemblies are of modular design and are constructed on site, see, e.g., U.S. Pat. No. 7,065,928. In other instances, prefabricated roof curb assemblies have been provided, which require no field assembly.
In many industrial applications, standing seam sloped metal roofs are deemed optimum. These roofs are made up of a series of elongated, side-by-side, interconnected panels and present a higher end and a lower end for water drainage. In the construction of these roofs, the panels are first placed in adjacency with the elongated side marginal standing seam components in close proximity. Thereupon, a seaming device is used to form laps or other types of joints by appropriate joining of the seam components. These joints can take a number of forms, e.g., simple overlaps, single or double locks, tees, snap locks, battens, or trapezoidal laps, see, e.g., http://www.nrca.net/roofing/Metal-roof-systems-for-steep-slope-applications-901.
Curb assemblies for standing seam metal roofs must be specially configured in order to accommodate the standing seams, because in many instances, the necessary roof openings have a lateral dimension which crosses one or more of the seams. Moreover, the curb assemblies must be easily installed in the field and designed eliminate or minimize leakage around the assemblies,